Prospective Randomized Controlled Trial of Three Bactericidal Antibiotic Combinations as Initial Empiric Antibiotic Therapy of Suspected Infection in Granulocytopenic Patients with Cancer. - The problems of broad spectrum antibiotic usage are formidable and include a high frequency of superinfections plus occasional renal damage. It was therefore decided to determine in an appropriate prospective, controlled trial whether gram-negative bacillary infections in granulocytopenic patients respond better to a penicillin-like drug (carbenicillin or cephalothin), an aminoglycoside (gentamicin), or the synergistic combination (carbenicillin-gentamicin for P. aeruginosa or cephalothin-gentamicin for Klebsiella or E. coli). Because of the large numbers of patient trails required, the BCRC has joined with an 18 hospital group to study this question under the auspices of the European Organization for Research on the Treatment of Cancer. The trial, begun Jan. 3, 1974, has included over 125 BCRC patients which represents about 33% of the total of 315 patients trials in the EORTC trial. Each of the three combinations have proven to be very effective with a combined response rate of 63% for bacteremias and 95% for other microbiologically or clinically documented infections. The study continues as outlined.